Tractor tread



March 12, 1929. Q HENNEUSE 1,704,857

TRACTOR TREAD 2 Sheets-Sheet 1 122.22% r (I L9 @660 2 1163 Lwk? L.

Original Filed Jan. 22, 1925 March 12, 1929. c. A. HENNEUSE TRACTORTREAD Original Filed Jan. 22, 1925 2 Sheets-Sheet I11 0821i??? W 4 6144W (9 it)? 176g Patented Mar. 12, 1929.

UNITED STATES 1,704,857 PATENT OFFICE.

CLARENCE A. HENNEUSE, OF SACRAMENTO, CALIFORNIA, ASSIGNOR TO HADFIELD-PENFIELD STEEL COMPANY, OF BUCYRUS, OHIO, A CORPORATION OF OHIO.

TRACTOR TREAD.

Refile of abandoned application. Serial No. 614,185, filed January 22,1923.

Serial No. 38,548.

The invention relates to tractor treads of the creeper type.

This application is a refile of my abandoned application Serial No.614,185, filed in the United States Patent Otlice, January 22, 1923.

An object of the invention is to provide a track which can be drivenover the ground with a minimum of resistance.

Another object of the invention is to provide a self-supporting track inwhich wear is reduced to a minimum, and which is capable of efficientoperation on uneven or marshy ground and sand.

A further object of the invention 1 s to provide a track mounting whichis a d ustable to maintain it in operative position to produce the abovementioned advantages.

A further object of the invention is to provide a track which lies in aflat are 1n contact with the ground, so that while the weight of thetractor is distributed over a large area the pressure at the center ofthe track is greater than at other points thereon, so that the tractormay be readily turned.

The invention possesses other advantageous features, some of which, withthe fore going, will be set forth at length in the followingdescription, where I shall outline in full, that form of the inventionwhich I have selected for illustration in the drawings accompanying andforming part of the present specititaition. In said drawings I haveshown one form of tractor of my invention but it is to be understoodthat I do not limit lnvself to such form, since the invention as setforth in the claims may be embodied in pluralityo-f forms.

lteferrii'ig to the said drawings;

Fig. 1 is a side elevation of the track and track frame;

Fig. 2 is a side elevation of several connected track links;

Fig. 3 is a longitudinal vertical section through several connectedtrack links;

Fig. 4 is a plan or top view of several connected track links;

Fig. 5 is a transverse vertical section through a link, taken on theline 55 Figure 4.

In the construction of a tractor of the creeper type, two endless treadsor tracks are usually emplo ed, one track being disposed on each side ofthe tractor. Each This application filed June track consists of a seriesof links or shoes 24, hinged together by the pins 25. The links areconstructed so that when hinged together, they form a track flexible inone direction and rigid in the opposite dircclion, that is, the linksare free to move to form a convex track as when passing over the idlers17, but cannot move to form a concave track. The links are preferablyformed so that the portion of the track which lies in contact with theground is slightly convex or curved downwardly and the driving sprocket19 engages the track at the center of the convexity. This trackconstruction produces a rigid track surface at all times, regardlessofithe condition of the ground surface, enabling the track to bridgesmall inequalities of the ground surface and to travel over soft groundand distributes the weight of the tractor evenly over soft ground, inboth instances reducing the rolling resistance to a minimum. Thecurvature of the track in contact with the ground enables the tractor tobe readily and quickly steered and permits it to smoothly operate overrough ground.

The sprocket wheel is of greater diameterthan the idler wheels and isprovided with teeth 21 which engage teeth 22 on the track links and isprovided with tread surfaces 23 at the pitch line which engage on therollway of the track, so that the sprocket also carries a large portionof the weight of the tractor, thus reducing the strain on the track andtrack supports.

The idler wheels 16 and 17 areadjustablc longitudinally so that thetrack may be moved to cause the sprocket to drive, at all times, on thelower run of the track. This is accomplished by insuring engagement ofthe sprocket teeth and lower track teeth in advance of any possibleengagement with the upper track teeth and in practice, engagement withthe upper track teeth is avoided. By this arrangement, the drivingstrain is localized on the stationary portion of the track which inengagement with the ground and no driving strain is placed on the linkconnections, during the time that adjacent links are in relative motion,as when moving onto or from the idler wheels. By eliminating unduestrain wherever there is relative motion, wear of the track is reducedto a minimum.

The track consists of a series of links or shoes 24 connected togetherby hinge pins 25. The shoe is preferably an integral casting comprisingside walls 41 connected together by suitable transverse members. Theside walls diverge from each other longitudinally forming a female endprovided with bosses 42 through which the hinge pin passes. The maleportion of the shoe is disposed substantially at the longitudinal centerof the shoe and is provided with a cored transverse member 43 which,when the shoes are assembled, fits between the bosses 42 of the nextadjacent shoe and the hinge pin passes through the bosses: and the memer 43. The member 43 is provided on its inner surface with an integraltooth 22, which is engaged by a sprocket tooth on the outer run of thetrack. The side plates extend past the tooth 22 on that side of thetooth remote from the bosses 42 and the inner surfaces of the extendedside walls are curved downwardly on the radius of the lower surface ofthe member 43, to form a hook which engages under the member 43 toprevent further rotational movement of one link with respect to theother. At the hook portion 45, the side walls are connected by a web 46,the inner surface of which is curved to conform to the curvature of thehook, forming a seat which bears against the outer side of the member 43when the links reach a position of parallelism or approximateparallelism. The parts of the shoes are preferably so positioned andproportioned that the extended portion of one shoe seats against thecentral transverse member 43 of the other shoe as the two shoes approachparallelism, and before they reach parallelism, so that the extendedtrack will lie in a shallow arc shown in Figure 1, but the parts may bepositioned and proportioned when desired, so that. the shoes may moveinto parallelism. In the first instance, a. slightly curved rigid trackis produced and in the other case, a straight rigid track is produced.

Each shoe is provided intermediate its ends with an integral bottomplate or tread plate 47, extending transversely of the shoe andextending beyond the side walls. The tread plate is provided on itsouter surface with a transversely extending rig or cleat 48 and betweenthe side walls, the plate is provided with an outwardly extending curvedportion 49, forming a grouser for increasing the tractive effect of thetrack on the ground. The tread plate 47 is of less length than the shoeand at its forward end is provided with an outwardly extending curvedlip 51, the inner surface of which lies in a circle of which the axis ofthe hinge pin passing through the adjacent end of the shoe is thecenter. At its rear end, the tread plate is provided with an upwardlycurved lip 52 the outer surface of which lies in a circle of which theaxis of the hinge pin passing through the center of the shoe is thecenter. In assembly, the hinge pin passing through the end sockets ofone shoe, passes centrally through the adjacent shoe, and the forwardlip 51 on one shoe under lies the rear lip 52 on the adjacent shoe, andboth lips are concentric with each other and have the axis of the samehinge pin as a center. The lips, which are in fact curved portions ofthe tread plates are preferably spaced apart radially, with relation tothe axis of the pin, a slight distance, so that they are not infrictional contact, but are sutliciently close together to form a ratherclose joint between the successive tread plates of the track. As onelink moves angularly with respect to the adjacent link, the hookedextension of one link moves down into the pocket within the link formedby the grouser 49 and the web 46 is provided with an outwardly extendingrig 54 which contacts with the surface of the pocket and limits theinclination of one link with respect to the adjacent link. Thepermissible angular movement is sufficient to permit the track to flexas its passes over the idler wheels on the track frame. The side walls41 of the shoes are provided at the female ends with track flanges 55,lying flush with the inner surfaces of the side walls and extendingoutwardly therefrom to the outer edges of the bosses 42. These trackflanges extend backward to adjacent the central transverse member 43 andat their ends, the outer surfaces thereof are curved, so that these ends56 make a close joint with the bosses 42 on the next succeeding shoe.The successive track flanges form a continuous track over which thetread surfaces 23 of the sprocket roll. By virtue of this constructionthere is provided a rigid track composed of one-piece shoes hingedtogether by pins which are not subjected to driving strain while theyare subjected to angular 1novement of the shoes. This not only producesa minimum of wear on the track but reduces the rolling resistance of thetractor to a minimum.

I claim:

1. An endless flexible tract-or track comprising a plurality ofconnected shoes, a pin bearing in each shoe at one end thereof, a pinbearing in each shoe adjacent the center thereof, the central bearing inone shoe being alined with the end bearing in the adj aceiit shoe, a pinextending through said bearings and a. seat on the other end of eachshoe adapted to engage the central bearing of the adjacent shoe.

2. An endless flexible tractor track comprising a plurality of connectedshoes, a pin bearing in each shoe at one end thereof, a pin bearing ineach shoe adjacent the center ltlt) llti thereof, the central bearing inone shoe being alined with the end bearing in the adjacent shoe, a pinextending through said bearings, the other end of each shoe beingmovable into engagement with the pin bearing in the adjacent shoe tolimit the angula r movement of each shoe with relation to the ad acentshoe.

3. An endless flexible tractor track, comprising a plurality of shoes,pins pivotally connecting said shoes, one of said pins being disposed atone end of one shoe and the other beiing disposed substantiallycentrally of said shoe, a tread plate on each shoe, a concave lip on oneend of said plate concentric with said first pin, and a convex lip onthe other end of said plate concentric with said second pin, the concavelip on one tread plate un- (lei-lying; the convex lip on the adjacenttread plate.

4. A tractor track shoe comprising side walls having bearings therein atone end, a transverse member connecting said walls and having a bearingtherein, a tread plate having a con ave lip concentric with the firstbearings and a convex lip concentric with the second bearing and a webconnecting the s de walls at a point remote from said bearing s.

I). A tractor track shoe comprising side wall having bearings therein atone end, av transverse member connecting said Walls and having ahen-inn; therein, and extending ab we said wails, a tread plateconnecting said walls, a concave lip on one end of said tread plate anda convex lip on the other end of said plate.

(3. A tractor track shoe comprising side walls having bearings thereinat one end, a transverse member connecting said walls and having! abearing therein, a tread plate having a depression therein between saidwalls connecting said walls and projecting beyond said walls, a concavelip on one end of said tread plate and a convex lip on the other end ofsaid tread plate.

In testimony whereof, I have signed my name to this specification.

CLARENCE A. HENNEUSE.

